Hey! Today we are next to a BMW and I'm going to show you how to
how to detect, what are the first symptoms of a bad battery.
So, you car is constantly monitoring the battery state
and if the battery is not drained by some circuit.
And before it happens, before your battery gets completely drained
or it's so old and damaged that you'll not be able to start your car
there will be some symptoms that will tell you
that you should service your car, that you should check your battery state.
The first thing is your welcome lights.
As you can see I have under the handles some LEDs
and only those LEDs are turning on.
My ring lights are not turning on right now.
If you have your headlights switch set to the AUTO position or to the ON position
you should see all the lights (in front and in the back of the car)
turning on when you're unlocking your car.
Of course if you have that setting enabled in your instrument cluster or in your iDrive system.
So that's the first tip that your battery should be checked.
The second thing that you can notice is
when your are using your radio with the engine OFF.
For example: you are cleaning your car and you turn on the radio just to
listen to some tunes.
And after few seconds or few minutes on the dashboard you can see the
batter yellow indicator that will tell you that the battery level is going low
and you should limit power consumption in order to preserve
power to start the engine.
So that's your clue number two.
The third thing that you should look for is the clock.
if it resets by itself that means that the car detected
low voltage in your system and it's preventing the battery to be drained.
There's a relay responsible for cutting off any system that is not essential to starting the car
(that includes your instrument cluster at the moment)
so those systems are shut off completely, they are not in standby mode
but their power is cut off from them
just to make sure that the battery will not drain, that the voltage will not drop
below level that is required to start your engine.
So next time you are in your car, you put the ignition on, you'll see the clock reset,
you know that this system worked correctly, it detected that the battery can go very low,
that the voltage will drop, and to prevent this it shut off some systems in your car.
So that was tip number three.
And of course to be 100% sure what's your battery state you can check the battery with
a battery tester. Such test will give you also a lot of information about the battery state
but just remember that the battery is not everything in the car.
You should also check the alternator - if it makes correct voltage.
If it can provide amps required to keep the battery charged all the time.
Also remember that big engines and diesel engines that have higher compression ratio
require a lot of amps to get the moving.
So the starter motor is draining more power
and if you're making a lot of short trips and you're constantly shutting the engine off and on
(also you have your glow plugs, your electric power steering)
there's a lot of systems that are consuming this power and it's a good idea to
take your car for a longer ride or keep it once a while connected to a battery charger
just to make sure that your battery is charged when you need it the most.
I hope that this will help you keep your car in the best condition.
Thank you for watching, give me thumbs up if this helped you
and check my other tutorials for more BMW and other brand tips.
See you soon.